Examples of a routing control method in a wireless mesh network include the Ad hoc On Demand Distance Vector (hereinafter referred to as “AODV”) routing and the routing protocol for low power and lossy networks (RPL) (see Non Patent Literature (NPL) 1, NPL 2, and NPL 3, for example).
Examples of a standard specification of a physical layer and a media access control (MAC) layer in communication apparatuses constituting the wireless mesh network include the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 and IEEE 802.15.4e (see NPL 5, for example).
On the other hand, the Association of Radio Industries and Businesses has defined standard specifications of radio equipment utilizing radio waves (see NPL 4, for example).
Patent Literature (PTL) 1 discloses a technique concerning transferring of a route request in a wireless mesh network. More specifically, when an intermediate router in a transmission path in the wireless mesh network receives a route request, a link cost of the transmission path between a source apparatus and the router is added to a metric of the route request, thereby updating the metric. Then, when the updated metric is smaller than a metric in a routing table held by the intermediate router, routing information to the source apparatus in the routing table is updated.